A used ball of cotton wool as a source of nosocomially-acquired hepatitis C infection.

BACKGROUND AND AIMS
An error involving the reuse of the same ball of cotton wool in stopping blood flow after venous blood collection from five antenatal women prompted further investigation and follow-up studies to rule out nosocomially-acquired blood borne viruses.


METHODS
The five women were screened for antibodies to the human immunodeficiency virus (HIV), hepatitis C virus (HCV) and hepatitis B surface antigen (HBsAg), using enzyme-linked immunosorbent assay (ELISA) /kits Murex HIV-1- ,2,0 (Murex Biotech, UK); ORTHO HCV 3.0 ELISA Test kit (Ortho Clinical Diagnostics, USA); and QUADRATECH CHECK 4-HBs one-step generation test kit (VEDALAB, France) respectively. The tests were repeated in 2005 on the five women, their husbands and twenty children, aged nine months to seven years borne by all the women within the period. Anti-HCV was detected in one out of the five women at the initial stage of the error (1997). No anti-HIV or HBsAg was found in any of the women. A repeat screening for anti-HIV, anti-HCV and HBsAg carried out seven years later (2005) on the five women, their husbands and twenty children aged nine months to seven years borne by all the women within the seven years revealed an HCV sero-conversion in two additional women. No anti-HCV or anti-HIV nor HBsAg was detected in any of the women, their spouses or their 20 offspring.


RESULTS
Anti-HCV was detected in one out of the five women at the initial stage of the error (1997). No anti-HIV or HBsAg was detected in any of the women. A repeat re-evaluation revealed an HCV sero-conversion in two additional women. No anti-HCV or anti-HIV nor HBsAg was detected in any of the women, their spouses or any of their 20 screened offspring.


CONCLUSIONS
This study provides evidence for the nosocomial transmission of HCV through the use of a contaminated ball of cotton wool. It also confirms the poor efficiency of sexual and vertical transmission of HCV and calls for improved hospital facilities and the use of skilled staff to perform essential duties.


Introduction
Hepatitis C is strictly a human infectious disease of the liver that is often asymptomatic (1) . Once established, chronic infection proceeds and can progress to fibrosis and cirrhosis after a period of many years of apparency. Globally it is estimated that 200 million people are infected with the virus with a larger percentage in Sub-Saharan Africa (1) .
Unlike the developed countries where hepatitis C virus has mainly been spread by blood-to-blood contact through transfusion of unscreened blood or blood products (before the emergence of HCVspecific diagnostic tests), and now predominantly via injected-drug use or sexual exposure (2) ; the primary sources of HCV infection in developing countries are unsterilized injection equipment and the infusion of inadequately screened blood and blood products (1) . Some studies have shown that people can be exposed to HCV via inadequately or improperly sterilized medical or dental equipment through accidental exposure to blood by means of accidental needle sticks or blood spatter to the eyes or open wounds.
interview with the women showed that none of them had been transfused within the past ten years.

Discussion
The seroprevalence of HCV in Nigeria is unclear, and its epidemiology, particularly in women and children, is yet to be established. Some recent studies have reported an HCV prevalence of 5% in apparently healthy blood donors (9) and 14.1% in diabetic patients 10 . However, unlike some developed countries where HCV transmission is predominantly associated with the sharing of contaminated needles and other drug paraphernalia by intravenous drug users (2) , the precise modes of transmission of HCV in Nigeria remains unclear (1) . Some authors have also suggested iatrogenic causes as a possible mode of HCV transmission in the region (2,3) . Furthermore, there is a paucity of data on the contributory role of household transmission, needle stick injuries, contaminated medical equipment, and blood spills in health care settings in the distribution of the virus in the country. Available data however, shows that each year, the reuse of injection equipment may cause 2 million infections with hepatitis C virus (HCV) worldwide (2) .
In many developing countries inadequacies in health care settings have often resulted in the recycling of some disposable items which may include needles and gloves. This enhanced by the dearth of skilled staff poses a major problem in the diagnosis and management of patients in many health care settings. In this study, the detection of antibodies to HCV in the two women who preceded the first woman screened as anti-HCV positive in 1997 provides evidence of a possible cross-infection emanating from the reused ball of cotton wool. Although the viral genotypes were not characterized (Njouom et al., 2003) (3) to determine their relatedness, the absence of a history of blood transfusion within the past ten years among the women rules out this mode as a possible means of spreading the infection. Similarly, the non-detection of antibodies to HCV in the spouses of the HCV seropositive women more than seven years after their acquisition of the infection also confirms the poor level of efficiency of sexual transmission of the virus (10,11) . Although the sexual transmission of HCV is well established, its efficiency of transmission has been shown to be poor (10) . Furthermore, the non-detection of anti-HCV among the eleven (11) surviving children borne by the three women with HCV antibodies also confirms the low level of vertical transmission of the virus (12,13) .
Some studies have shown that HCV can survive outside the body for up to 3 months, and its RNA remains stable at room temperature for several hours (14) . In addition, HCV has been shown to withstand a high level of acidity for hours. These features are all likely to have favoured the acquisition of the virus by means of the contaminated cotton wool.

Conclusions
This study implicates a contaminated ball of cotton wool as a source of transmission of HCV and supports reports of iatrogenic causes as the main source of transmission of blood borne viruses in most developing countries. It also provides evidence in support of the poor sexual (10,11) and vertical transmission (13) of HCV and makes need for the use of skilled staff and improved laboratory facilities in developing countries.